Sequestering Carbon Deep Within the Earth

This post is by Scott Anderson, an attorney and senior policy advisor at the Environmental Defense Fund. It's the second in a three-part series on carbon sequestration – storing carbon or carbon dioxide (CO2) in soils, trees, geological formations, and oceans.

To stop global warming, the U.S. must substantially move away from carbon-emitting fossil fuels to clean renewable energy. But a transition of this magnitude takes time. Right now this country is heavily dependent on coal for electricity, and traditional coal plants are none too clean.

How do we stop global warming while renewable technologies to meet our energy needs are still under development? Part of the answer may lie in an emerging transition technology called Carbon dioxide (CO2) Capture and Storage (CCS). The idea behind CCS is to capture the CO2 from industrial processes like coal plants, and then store it in deep geological formations.

CCS can dramatically reduce carbon emissions from coal plants. The IPCC's Special Report on Carbon Dioxide Capture and Storage says that "a power plant with CCS could reduce CO2 emissions to the atmosphere by approximately 80-90% compared to a plant without CCS." This is after taking into account the extra energy needed to capture and compress the CO2.

The United States has the geological capacity to store the emissions from its coal-fueled plants in depleted oil and gas reservoirs for several decades.

Capacity in other geological reservoirs is estimated to be in the hundreds of billions of tons (500 billion tons of capacity), enough to store current levels of domestic emissions for over 300 years.

Worldwide, according to the IPCC, there is a potential capacity in geological formations to store at least 545 gigatons.

How Geo-Sequestration Works

In geological sequestration, compressed CO2 is injected into porous rock formations. It's very much like pouring water into a glass of marbles, where the water represents liquefied CO2 and the space between the marbles represents available pore space in the rock found in deep saline formations or depleted oil and gas reservoirs.

The technology for injecting CO2 into depleted oil and gas reservoirs already exists because of a process called Enhanced Oil Recovery (EOR), which has been in use for over 30 years. With EOR, oil not recovered in the initial withdrawal process is pushed to the surface by injecting CO2.

Safety and Regulation

But the CO2 in EOR isn't necessarily stored for the long-term – it's just injected. For geologic sequestration, the carbon ought to be stored for 1000 years or more without leaking back into the atmosphere. Not all depleted gas and oil reservoirs can meet this requirement.

Suitable sites, for example, must lie below and isolated from fresh water supplies, and ideally should have one or more layers of sealing caprock to prevent the CO2 from seeping to the surface. The requirements are still being explored in dozens of ongoing projects.

There is also ongoing work on developing regulations to select and monitor suitable sites. On January 31, I testified before the Senate Committee on Energy and Natural Resources on this topic (see full testimony [PDF]). Although CCS is ready to begin deployment today, widespread adoption won't take place until the regulatory and commercial framework has been fully implemented, and this could take quite a few years. We have called upon policymakers to develop a sound regulatory framework as rapidly as possible.

A Critical Transition Technology

Some argue that CCS diverts attention from the development of clean energy resources, but in fact CCS is a critical transition technology. Coal plants and other industries will continue to emit CO2 while alternative energy sources are developed and adopted. Earlier this year, the Commission of the European Communities issued a directive [PDF] emphasizing the importance of CCS in halting climate change:

Energy efficiency and renewables are in the long term the most sustainable solutions both for security of supply and climate. However, we cannot reduce EU or world CO2 emissions by 50% in 2050 if we do not also use the possibility to capture CO2 from industrial installations and store it in geological formations (carbon dioxide capture and storage, or CCS).

We're not champions of coal at EDF, but we are realists. Coal will be used to produce electricity for the foreseeable future, so we need technologies that allow coal to be used in a manner that avoids significant greenhouse gas emissions.

9 Comments

There seems to be quite a bit of evidence that CO2 is a very small driver of global warming, that it FOLLOWS by hundreds of years the warming after the end of the ice age. The processes causing global warming are not well understood, and they appear to be natural. (we've had many global warming and cooling periods). Why are so many reputable scientists saying man is NOT the cause of this global warming, and why does it appear that the recent temp rise has peaked?

Ms. Canter, Surely you would,as an information officer in your organization quest for all points of view and points of science to have a fair and balanced process to bring the public the very best of information.

The climate science folks you support as the only paradigm have many problems with their assumptions and that has been tasked by many science folks who also have enough intellect to look at the evidence of the past.

Your Mr. Wangs assertion that those in the Inhofe report just work for the oil company is just a journalistic emotive ploy that really does just belong in the Star.

Responsible science folks do not need to place the bad guy in their science information to assure that their faction dis-avows anything that is not approved by their Phd. person.

So,just for the record, I definitely do not get any process from the oil companies except for interference in my office and the deaths of many,so you might assume I have an ax to grind and would suppot any position that makes them the bad guy,but I cannot ,as they are responsible for many improprieties,but certainly not Global Warming.

If the science departments that churned out the "Climate Scientists" had been trained to proper grid science,the controversies would be much smaller and economic damage would not be such an issue.

NASA folks are tier two scientists to me and they are not given so much information that would change their paradigm for a very good reason by a contingent of other folks that do not have your best interest in mind.

I am not from that faction,and they have caused my faction untold trouble on the planet,they really do not want things fixed.

So for the record again,my contingent does want things fixed and we work diligently everyday in that direction.

As with the carbon sequestration ,petro price and military actions to protect that paradigm and those that actually do task for their directives when they beat everyone to death with GHG mis-information to play right into their hands need it beat into their consciousness daily so as to put a big crack in their loop.

We desire and demand less carbon output,we desire and demand that our aquifers not be poisoned daily,we desire and demand the "Faction" I speak about stop putting flouride in all of the consumables for the slow task down of intellect and the infusion of mercury products into our children to create a further tasking down of intellect and to stop spraying the H viuses that now have killed 50 percent of the bees so needed for our flowering foods from what we call lifters that can be seen all over if you know how to look for them,an F-16 is a Falcon and the lifters that are anti grav that spray are Tigers.

So while every science tasker is busy screaming about GHG,Rome burns and more and more people and animals are killed down daily.

Please see some of my other taskings on this 4-11 blog for some ponderings about grid science as that grid has been used against factions and countries for a long time now,along with their playing with crop circles.

"Proper" crop circles are ones that science folks inspect and find no foot inervention and stalks bent without breaking and enhanced growth also. They are built at grid nodes and the Nitrogens frequency that provides that gas for this planet is engaged at that spot and so enhanced growth and that little tid-bit is just to flow into the tid-bit that oxygens flow constantly into the planet also and the funny thing is that the Lifter boys do not get as much efficiacy from their spray because that node ozone cleans the air and kills the much of the viral load they put out.

Just like the "Light Frequency" that cleans up your favorite hot tub and gives your fav hair stylist their clean cabinet. Why even Wal-Mart uses light frequency ozone in their meat cases to deplete bacterial and viral load.

Guess what the secret is about hydrogens frequency???

They( the faction I speak to) just shudders and kills everyday to keep that secret in GE's safe.

Is there any evidence that reducing CO2 concentration in the atmosphere has any effect on global temperatures? The GHG theory was developed during a warming period from 1975 to 1998. If the theory had been curve fitted for the period of 1940 to 1975, it seems an equally strong case might be made that increasing CO2 concentration cools the climate, and, in fact the scientists of the day thought that cooling was the big climatological crisis.

And, a similar argument might be made for 1998 to the present. When observations of warming or cooling can be made in the face of increasing concentration it is easy to understand why those scientists who count sunspots and sucessfully predict future climate changes might have it right. Why is it, that none of the IPCC models have ever correctly predicted anything correctly except after fiddling with the parameters.

I see you removed both of my posts. C'mon… a little well needed truth concerning the bloviates touting bogus "peer review" seem to be needed now.

"What a man believes upon grossly insufficient evidence is an index into his desires — desires of which he himself is often unconscious. If a man is offered a fact which goes against his instincts, he will scrutinize it closely, and unless the evidence is overwhelming, he will refuse to believe it. If, on the other hand, he is offered something which affords a reason for acting in accordance to his instincts, he will accept it even on the slightest evidence. The origin of myths is explained in this way." Bertrand Russell Global warming = myth

Simply plotting a yearly average temperature over time and measuring the slope of the resulting figure does not give a truth about climate change. The climate system is a very complex, non-linear system with countless feedback mechanisms which by themselves are pretty complex. For (simple) example, the carbon dioxide content of ocean water is in equilibrium with the atmosphere's carbon dioxide pressure, which causes the ocean to acidify with increasing atmospheric carbon dioxide. Regardless of global warming or sea level rise, it might not be a slam dunk idea to mindlessly emit carbon dioxide into the atmosphere just because we do not fully understand the consequences. As for IPCC climate models, they are very similar to the models used to predict weather. Meteorologist are very reluctant to predict weather for more than a week in advance, because the model is not accurate at such a range. IPCC predicts the climate for 50-100 years ahead with those models. Of course none of them correctly predict anything.

Meaning that "Peer Review" when jaded by instinct and personal opinion instead of relying on established facts based on study impunes the whole scientific community and is the pathway to getting nothing done when we now, more than ever, need as much traction as possible on this growning problem. Sorry for the obscurity… Cheers

I think you have made some good points here. Not many people would actually think about this the way you just did. Im really impressed that theres so much about this great subject thats been uncovered and you did it so well. Good one, man! Really fantatic stuff here.

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